The present invention relates to a device for feeding a printing medium such as a paper sheet and an OHP sheet into a computer output terminal apparatus in the form of an image reproduction apparatus to effect hard copying or image reproduction.
Conventionally, the printing medium wound in a roll or web is sandwiched between a feed roller and a pinch roller to simply feed forward the same to an operation start point in the image reproduction apparatus. The pinch roller is not released during the image reproduction operation. Alternatively, the pinch roller is released by means of a motor or solenoid which requires a power source.
In the printing medium feeding device, the feed roller and the conventional pinch roller are provided to sandwich the printing medium to feed the same to the operation start point or position in the image reproduction apparatus. After the feeding, it is desired that the fed medium is made free of contact with either of the pinch roller and the feed roller. If the feed roller and the pinch roller are not spaced from the printing medium, the printing medium may receive mechanical vibration and excessive pressure due to dimensional error of components including the feed roller and the pinch roller, thereby reducing the image quality. In addition, power or energy may be wasted during the image forming due to unnecessary application of pressure in the image reproduction apparatus.
In another prior art device, in order to remove the feed roller and the pinch roller from the printing medium, an actuator is used such as a motor or a electromagnetic solenoid, which requires a power source. However, the use of these actuators increase cost, reduce assembling productivity due to increase in components, and degrade the reliability of the device.